Moritz Grossmann RAT One (Unique Piece, Chinese Zodiac Collection)

The RAT One is the only gold model in the 12-piece Chinese Zodic collection created by Moritz Grossmann exclusively for Christie’s online auction from 18 November – 2 December 2019.

This one-off piece made from rose gold, highlights a hand-painted as a miniature drawing according to the artistic design of Laura Heyne. The offer is also including original painting of the artist. RAT One is all about the year 2020, because this is the year of the rat in Chinese astrology.

As a highlight piece of the Zodiac collection, this one-off piece is furnished with a rose gold casing and celebrates the rat, which is the first sign of the Chinese zodiac.

Intelligent, beautiful and faithful – the artist sees these qualities in the rat. Thanks to her personal love of rats, the choice of motif was not too difficult. She herself used to keep a rat as a pet and learned to love these qualities.

By arranging several rats in a circle, the artist symbolises the good social behaviour of the animals and expresses their beauty through the flowers. The hands, handcrafted in the manufactory, are annealed over an open flame in the typical Moritz Grossmann brown-violet colour and harmonise with the solid silver dial.

The rat is the first of the Chinese zodiac signs.
Years of birth under the sign of the rat: 1936, 1948, 1960, 1972, 1984, 1996, 2008, 2020

The model was manufactured in High Artistic Finish with the calibre 100.1. The movement is visible though the generous transparent back made of sapphire crystal with an antireflective coating on one side. The pillar movement with well-proportioned components made of untreated German silver with various finishes forms different levels. On the characteristic 2/3 plate with broad horizontal ribbing, the signet is engraved by hand. The Grossmann balance is visible in the curved plate cut-out and is borne by the stepped, hand-engraved balance cock with the typical fine micrometer screw.

Technical details


Manufacture calibre 100.1, manually wound, adjusted in five positions
Diameter: 36.4 mm, height: 5.0 mm
No. of parts 198
No. of jewels 20 jewels, 3 of which in screwed gold chatons
Escapement Lever escapement
Oscillator Shock-absorbed Grossmann balance with 4 inertia and 2 poising screws, Nivarox 1 balance spring with No. 80 Breguet terminal curve, Gustav Gerstenberger geometry
Balance Diameter: 14.2 mm, frequency: 18,000 semi-oscillations per hour
Power reserve: 42 hours when fully wound

Hours and minutes, Grossmann winder with pusher

Three-part, precious metal
Diameter: 41.0 mm, height: 11.35 mm
Crystal/display back: Sapphire crystal, antireflection-coated on one side
Operating elements: Crown in 750/000 gold to wind the watch and set the time, pusher in 750/000 gold to start the movement

Solid silver, hand-painted
Hands: Manually crafted from steel, annealed to a brown-violet hue

Hand-stitched calf strap with prong buckle in precious metal

Special features
Grossmann balance; hand setting override and start of movement with lateral pusher; space-saving modified Glashütte stopwork with backlash; adjustment with Grossmann micrometer screw on a cantilevered balance cock; Pillar movement with 2/3 plate and frame pillars in untreated German silver; 2/3 plate, balance cock, and escape-wheel cock engraved by hand; broad horizontal Glashütte ribbing; 3-band snailing on the ratchet wheel; raised gold chatons with pan-head screws; separately removable clutch winder; stop seconds for hand setting